1、导入依赖
<!-- 使用table api 引入的依赖,使用桥接器和底层datastream api连接支持-->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-table-api-java-bridge_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<!--如果需要在本地运行table api和sql 还需要引入一下依赖-->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-table-planner-blink_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-scala_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<!--如果想实现自定义的数据格式来做序列化,需要引入一下依赖-->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-table-common</artifactId>
<version>${flink.version}</version>
</dependency>
<!--连接外部数据格式解析,采用csv方式来解析-->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-csv</artifactId>
<version>${flink.version}</version>
</dependency>
1.1、从文件中输入
路径:input/clicks.txt
Bob,./test/111,1000
Bob,./test/222,1000
Bob,./test/333,1000
Bob,./test/444,1000
2、表转流输出
package com.flinktest.wc;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.EnvironmentSettings;
import org.apache.flink.table.api.Table;
import org.apache.flink.table.api.TableEnvironment;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;
public class CommApiTest3 {
public static void main(String[] args) throws Exception{
// 创建执行环境的两种方式,流方式 & 表方式
// 1 创建执行环境(流方式创建)
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
env.setParallelism(1);
StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
// 2 创建执行环境(表方式创建) 基于alibaba 的 blink planner实现
// EnvironmentSettings settings = EnvironmentSettings.newInstance()
// .inStreamingMode()
// .useBlinkPlanner()
// .build();
// TableEnvironment tableEnv = TableEnvironment.create(settings);
// 3 创建一张连接器表(输入表)
String createInDDL = "CREATE TABLE clickTable (" +
"user_name STRING, " +
"url STRING, " +
"ts BIGINT " +
") WITH (" +
" 'connector' = 'filesystem'," +
" 'path' = 'input/clicks.txt'," +
" 'format' = 'csv'" +
")";
tableEnv.executeSql(createInDDL);
// 执行聚合统计查询转换
Table eggResult = tableEnv.sqlQuery("select user_name,COUNT(url) as cnt from clickTable group by user_name");
// table 转流输出,聚合统计是动态表,所以使用Changelog的方式才能输出
tableEnv.toChangelogStream(eggResult).print("egg");
env.execute();
}
}